The development of improved liquid crystal ("LC") flat-panel displays is an area of very active research, driven in large part by the proliferation of and demand for portable electronic appliances, including computers and wireless telecommunications devices. Moreover, as the quality of LC displays improves, and the cost of manufacturing declines, it is projected that LC displays ("LCD"s) may eventually displace conventional display technologies, such as cathode-ray-tubes.
One aspect of LCDs, to which significant research has been directed in recent years, is the demand for such displays to provide full-color images. It is quite possible that LCDs capable of displaying full-color images, at full-motion video rates, will eventually displace conventional cathode-ray tubes in television and computer display applications. In addition, it is desirable that LCDs be capable of displaying stereographic, or "three-dimensional" "virtual reality" systems, which can be used not only for entertainment purposes, but as tools in such diverse fields as medicine, manufacturing, and service/repair. Several characteristics of conventional LCD materials and methods of manufacturing such displays, however, present barriers to an efficient method of manufacturing 3-D displays.
LCDs are constructed by trapping a thin film of LC between two substrates of glass or transparent plastic. The conventional method of trapping the LC between the substrates is to first join the substrates and then introduce a LC into the interstitial region(s) formed therebetween. The substrates are usually manufactured with transparent electrodes, typically made of indium tin oxide ("ITO"), to which electrical "driving" signals are coupled. The driving signals induce an electric field which can cause a phase change or state change in the LC material; the LC exhibiting different light-reflecting characteristics according to its phase and/or state.
Conventional LCD manufacturing techniques introduce a LC material having an intrinsic polarity into the region between the display substrates. For 3-D images, however, it is desirable that the LCD include regions of LC material having different polarities, such as left-hand and right-hand circular polarities; the regions of left-hand circular polarity can be used to display a first image simultaneously with the display of a second image using the regions of right-hand circular polarity. An observer can use, for example, a pair of eyeglasses having left and right polarizing lenses corresponding to the polarities of the first and second images to see the stereographic image composed of the first and second images. The practical difficulty of manufacturing 3-D LCD displays, using conventional techniques, is that the LC material introduced into the region between the substrates has the same polarity for each individual microscopic pixel (or sub-pixel) of the display.
Therefore, what is needed in the art is a LCD wherein LC materials having different polarities may be introduced into different regions, or cells, between the LCD substrates. There is a further need in the art for an easily manufacturable stereographic LCD display system.